Bulk material cargo containers are conventionally utilized, at different times, to house or contain different fluid-like or flowable bulk cargo materials, such as, for example, dry bulk chemicals, powdered and pelletized resins, coffee beans, flour, grains, rice, sugar, and the like. The bulk material cargo containers are integrally formed within, for example, the cargo holds of ships, trucks, railroad cars, and the like, whereby the bulk cargo materials can readily be shipped or transported from one location to another. Alternatively, the bulk material cargo containers are utilized to temporarily store bulk cargo materials at a particular location prior to the continued transportation or shipping of the bulk cargo materials, or still further, prior to the discharge or unloading of the bulk cargo materials from the bulk material cargo containers. Since different bulk cargo materials are shipped or transported within a particular bulk material cargo container at different times, it is imperative that the bulk material cargo containers effectively be clean so as not to contaminate the materials, comprising a particular bulk material cargo load, with any residual materials which may have remained within the bulk material cargo container from a previously shipped or transported bulk material cargo load. Accordingly, in order to eliminate the necessary cleaning of each bulk material cargo container after a particular bulk material cargo load has been unloaded or discharged from a particular one of the bulk material cargo containers, it has become conventional within the industry to employ removable bulk material container liners within the cargo holds or the bulk material cargo containers whereby, after a particular bulk material cargo load is delivered to its destination and discharged or unloaded, the bulk material cargo container liner is simply removed from the bulk material cargo container, thereby again rendering the bulk material cargo container usable for carrying another bulk material cargo load without requiring a significant amount of cleaning of the bulk material cargo container.
Examples of bulk material cargo container liners as used within bulk material cargo containers for shipping or transporting fluid-like or flowable materials are disclosed within U.S. Pat. No. 5,657,896 which issued on Aug. 19, 1997 to Matias, U.S. Pat. No. 5,542,563 which issued on Aug. 6, 1996 to Matias, U.S. Pat. No. 5,489,037 which issued on Feb. 6, 1996 to Stopper, U.S. Pat. No. 5,421,476 which issued on Jun. 6, 1995 to Matias, U.S. Pat. No. 5,222,621 which issued on Jun. 29, 1993 to Matias, U.S. Pat. No. 5,193,710 which issued on Mar. 16, 1993 to Podd, Sr. et al., U.S. Pat. No. 5,152,735 which issued on Oct. 6, 1992 to Podd, Jr. et al., U.S. Pat. No. 5,137,170 which issued on Aug. 11, 1992 to Matias, U.S. Pat. No. 4,884,722 which issued on Dec. 5, 1989 to Podd, U.S. Pat. No. 4,541,765 which issued on Sep. 17, 1985 to Moore, and FRENCH Patent 2,461,661 which was published on Jun. 2, 1981 in the name of Bac. While the aforenoted removable bulk material cargo container liners have obviously performed satisfactorily from an overall point of view in connection with the achievement of their primary objectives, such removable bulk material cargo container liners have exhibited several operational and structural difficulties. For example, as disclosed within the aforenoted U.S. Pat. No. 5,489,037 which issued to Stopper, U.S. Pat. No. 5,152,735 which issued to Podd, Jr. et al., U.S. Pat. No. 4,884,722 which issued to Podd, and FRENCH Patent 2,461,661 which issued to Bac, bracing systems comprising structural bulkheads, reinforcing straps, and rigid cross-beams, are employed.
More particularly, the structural bulkheads are interposed between the rear end wall portions of the bulk material cargo container liners and the rear end walls of the bulk material cargo containers, which are conventionally formed by means of a pair of pivotal doors, such that the loads or hydrostatic head forces, characteristic of the bulk material disposed internally within the bulk material cargo container liners, are not transferred to the rear doors of the bulk material cargo containers. In addition, strapping systems and reinforcing cross-beams are sometimes additionally utilized in conjunction with the structural bulkheads so as to secure and effectively support the structural bulkheads with respect to the bulk material cargo container as well as with respect to the bulk material cargo container liner. It is therefore readily appreciated that these systems are structurally complex and time-consuming to erect or install. In addition, such bulkheads add a significant amount of weight to the gross weight of the cargo load to be transported or shipped, and they do not always enable the viewing of the interior of the bulk material cargo container liner and the bulk material cargo container whereby, for example, monitoring of the inflation or expansion of the bulk material cargo container liner, and the charging of the bulk materials into the bulk material cargo container liner, are not always able to be readily achieved.
Continuing further, as disclosed within all of the aforenoted Matias patents, relatively complex reinforcing systems, comprising a plurality of reinforcing straps disposed both internally and externally of the bulk material cargo container liners, are utilized. While such reinforcing systems ostensibly serve to in fact reinforce the rear end wall portion of the bulk material cargo container liner, such systems pose potentially defective problems, and in addition, such reinforcing systems are costly to fabricate and implement. For example, it is noted that a plurality of vertically spaced, horizontally oriented external reinforcing straps, and a plurality of horizontally spaced, vertically oriented external reinforcing straps are secured to the external surface of the rear end wall portion of the bulk material cargo container liner so as to effectively crisscross each other at a plurality of intersection locations and thereby form a checker-board arrangement. Still further, a plurality of obliquely oriented tensioning straps are disposed internally within the bulk material cargo container liner wherein first end portions of the internally disposed tensioning straps are fixedly secured to the plurality of externally disposed reinforcing straps at the intersection locations thereof, while second end portions of the plurality of internally disposed tensioning straps are fixedly secured to predetermined locations upon the floor portion of the bulk material cargo container liner. In view of the fact that the internally disposed tensioning straps effectively comprise lineal members, the cross-sectional area of each tensioning strap is extremely small. Accordingly, the resulting interactive clamping force defined or generated between each tensioning strap and the bulk material disposed internally within the bulk material cargo container liner is correspondingly small whereby the securing, holding, or restraint forces, acting upon the rear wall portion of the bulk material cargo container liner, are only a function of the floor-anchoring attachment assembly, the strapping tension, and the rear wall-anchoring attachment assembly defined upon the rear wall portion of the bulk material cargo container liner at each crisscrossed intersection.
A need therefore exists in the art for a new and improved bulk material cargo container liner, for use in conjunction with bulk material cargo containers, and within which bulk cargo materials are to be accommodated for shipping, transportation, and storage purposes, wherein the bulk material cargo container liner must necessarily comprise an internal structural system which will be capable of providing enhanced restraint forces for impression upon the rear wall portion of the bulk material cargo container liner so as to effectively restrict or prevent the tendency of the rear wall portion of the bulk material cargo container liner to experience or undergo any rearwardly oriented outward bulging under the influence of the substantially large hydrostatic head which is normally or inherently impressed upon the rear wall portion of the bulk material cargo container liner by means of the bulk cargo material contained within the bulk material cargo container liner as a result of the bulk cargo material having been charged into or deposited within the bulk material cargo container liner.